1. Field of the Invention
The present invention is generally related to a method of manufacturing a helical stent having an orthogonal end relative to a longitudinal axis of the stent, as well as to a helical stent having an end that is orthogonal to the longitudinal axis of the stent.
2. Background of the Invention
A stent is typically a hollow, generally cylindrical device that is deployed in a body lumen from a radially contracted configuration into a radially expanded configuration, which allows it to contact and support a vessel wall. A plastically deformable stent can be implanted during an angioplasty procedure by using a delivery system that includes a balloon catheter bearing a compressed or “crimped” stent, which has been loaded onto the balloon. The stent radially expands as the balloon is inflated, forcing the stent into contact with the body lumen, thereby forming a support for the vessel wall. Deployment is effected after the stent has been introduced percutaneously, transported transluminally, and positioned at a desired location by means of the balloon catheter.
Stents may be formed from wire(s), may be cut from a tube, or may be cut from a sheet of material and then rolled into a tube-like structure. While some stents may include a plurality of connected rings that are substantially parallel to each other and are oriented substantially perpendicular to a longitudinal axis of the stent, others may include a helical coil that is wrapped around the longitudinal axis at a non-perpendicular angle. Helical stents tend to have ends that are not perpendicular to the longitudinal axis due to the pitch of the helix. To square off the ends of a helical stent, the last turn at either end may include a wave form that includes waves of varying amplitudes. However, by varying the amplitudes of the waves, the stent may exhibit non-uniform behavior as the stent is crimped onto a balloon and/or expanded at the deployment site.